One of the problems affecting synchrotrons and colliders is that the relativistic particles, which circulate within the ring, emit synchrotron radiation. These radiations can deteriorate the vacuum by desorbing from the wall gases as H2, CO2, CO, H2O and CH4 [1-2]. A solution for this problem may be the installation of cryosorbers in the collider cryogenic elements operating at low temperatures. Several cryosorbers have been studied in the past [3-6]. In this work we present a Temperature Programmed Desorption (TPD) study on H2 adsorption on multiwalled carbon nanotubes (MWNT) at very low pressure (10-6 Torr) and temperature (12-30 K). A comparison with charcoal shows that MWNTs are more effective as hydrogen molecule cryosorbers.
1. V. Baglin, Vacuum Performances Estimation of the cryosorbers to be installed in the LHC LSS, Vacuum technical Note 04-06 EDMS N0: 478338, CERN – AT division (2004)
2. B. Angerth, F. Bertinelli, J.-C. Brunet, R. Calder, J. Gomez-Goni, O. Grobner, A. Mathewson, A. Poncet, C. Reymermier and E. Wallen, the Cold vacuum System of the Large Hadron Collider, CERN, AT Division 1211 Geneva 23, 2467.
3. Takefumi Horiuchi and Tsutomu Ooi, Cryogenic properties of composite materials, Cryogenics 35, 677 (1995)
4. V.V. Simonyan, J. K. Johnson, Hydrogen storage in carbon nanotubes and graphitic nanofibers, Journal of Alloys and Compounds 330, 659 (2002)
5. S. Hynek, W. Fuller, J. Bentley, Int. J. Hydrogen Energy 22, 601 (1997)
6. J.S. Noh, R.K. Agarwal, J.A. SchWARZ, Int. J. Hydrogen Energy 12 693 (1987)
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